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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Effect of mud, manure and other adhering material on slaughter cattle shrinkage

Ramsey, Herbert E. January 2011 (has links)
Digitized by Kansas Correctional Industries
122

Economic possibilities of backward vertical integration by a Kansas commercial feedlot company

Bratcher, Stanley W January 2010 (has links)
Digitized by Kansas Correctional Industries
123

Leptospira spp. e Brucella spp. em feitos e oócitos colhidos de vacas no momento do abate /

Magajevski, Fernanda Senter. January 2007 (has links)
Orientador: Raul José Silva Gírio / Banca: Luís Antonio Mathias / Banca: Angela Cleusa de Fatima Banzatto de Carvalho / Banca: Sílvio Arruda Vasconcellos / Banca: Sonia Regina Pinheiro / Resumo: A leptospirose e a brucelose são duas das mais importantes enfermidades da esfera reprodutiva em bovinos, podendo ser transmitidas durante a utilização de técnicas de reprodução assistida. Este trabalho visa pesquisar a presença e a ação da Leptospira spp. e da Brucella spp. em fetos e oócitos bovinos. Foram colhidas amostras do sangue de 512 vacas encaminhadas para o abate em um frigorífico do Estado de São Paulo; dessas, 212 foram utilizadas para a pesquisa de Leptospira spp. e Brucella spp. nos fetos, e 300 foram utilizadas para pesquisa desses agentes no líquido folicular e nos oócitos. Amostras de órgãos fetais (rim, fígado, baço e pulmão), conteúdo estomacal fetal, placenta materna e líquido folicular (LF) foram submetidas às técnicas de cultivo em meio próprio para crescimento de Leptospira spp (Fletcher) e Brucella spp. (Brucella-ágar) e à técnica de reação em cadeia da polimerase multiplex (PCRm) para ambos os agentes. Os oócitos provenientes de vacas sorologicamente negativas para leptospirose e brucelose foram maturados em meio contaminado com Leptospira interrogans sorovar Pomona, sendo uma parte em meio sem antibiótico e outra com antibiótico. Os oOOtos provenientes de fêmeas sorologicamente positivas para leptospirose foram maturados em meio de maturação esterilizado, sendo uma parte sem antibiótico e outra com antibiótico, e oOOtos provenientes de vacas sororreagentes para brucelose foram maturados em meio estéril sem antibiótico. Após a maturação, parte dos oócitos foi encaminhada para PCRm, e outra parte fixada em lâmina e corada pelas técnicas de Levaditi e- imunoistoquímica para a pesquisa de Leptospira spp.. Entre as 512 vacas avaliadas, 234 (45,70%) foram reagentes na soroaglutinação microscópica (SAM) e 50 (9,76%) sororreagentes na prova do antígeno acidificado tamponado (AA T), sendo 34 (6,64%)...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Leptospirosis and brucellosis are two of the most important diseases of the reproductive sphere in bovines, being able to be transmitted during the use of assisted reproduction techniques. This work aims to research the presence and the action of Leptospira spp. and Brucella spp. in bovine fetus and oocytes. Blood samples of 512 slaughtered cows, were collected in a slaughterhouse in the State of São Paulo. Of these, 212 were used for the research of Leptospira spp. and Brucella spp. in the fetus, and 300 were used for research of these agents in the follicular liquid and the oocytes. Samples of fetal organs (kidney, liver, spleen and lung), fetal stomach content, maternal placenta and follicular liquid (FL) were submitted to the techniques of cultivation for the growth of Leptospira spp. (Fletcher) and Brucella spp. (Brucella-agar) and the technique of PCRmultiplex for both agents. The oocytes from serological negative cows for leptospirosis and brucellosis were matured in a contaminated media with Leptospira interrogans serovar Pomona, being a part without antibiotic and another one with antibiotic. The oocytes from serologically positive females for leptospirosis were matured in a sterilized environment, being a part without antibiotic and another with antibiotic and oocytes from cows seroreacting, from brucellosis were matured in sterile environmenta without antibiotic. Afier the maturation, part of the oocytes were directed to PCRm and another part settled in the blade and dyed by the Levaditi technique and immunohistochemical for the research of Leptospira spp.. Among the 512 evaluated cows, 234 (45,70%) reacted to the microscopic seroagglutination (MAT) and 50 (9,76%) reacted to the Rose Bengal Plate Test (RBPT), being 34 (6,64%)...(Complete abstract, access undermentioned eletronic address) / Doutor
124

The effect of rearing environment on sexual behavior of young beef bulls

Lane, Sherry M January 2011 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
125

Determining the nutritional and economic impact of feed waste when wintering beef cows in central Alberta

Yaremcio, Barry 11 1900 (has links)
Two experiments measured winter feed waste when cows were fed forage on snow. In the first experiment, feed waste was different (P<0.01) when alfalfa meadow brome mixed hay was fed by bale unroller or bale processor; waste was12.9% vs.19.2%, protein losses were 23.3% and 21.5% respectfully. Feed waste, nutrient replacement and additional equipment costs increased winter feeding costs by $52.50 and $56.25 per head respectfully for a 175 day feeding period. Hay processed into portable bunk feeders, experienced 0% feed waste. In the second experiment, feed waste when barley cereal silage fed either as high moisture round bale silage or chopped pit silage was fed on snow was not different (P>0.05) at 23.2% and 26.8% respectfully. When chopped barley cereal silage or high moisture round bale silage was fed into bunks, feed waste was 0%. Protein losses were 27.1% and 24.2% for the pit and round bale silage. Feed waste, nutrient replacement and additional equipment costs increased winter feeding costs by $164.50 for pit silage and $126.00 for bale silage over a 175 day feeding period. / Animal Science
126

Effects of dietary vitamin A restriction on the site of fat deposition and fatty acid composition of growing cattle

Gorocica-Buenfil, Milton A., January 2006 (has links)
Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 193-206).
127

EFFECT OF ENERGY SUPPLEMENTATION FROM BY-PRODUCT FEED PELLETS ON PRODUCTIVITY AND NUTRIENT UTILIZATION OF CATTLE GRAZING STOCKPILED CRESTED WHEATGRASS (Agropyron cristatum L.)

2013 September 1900 (has links)
Three experiments were conducted to determine the effects of source (experiment 1), frequency, and level (experiments 2 and 3) of energy supplementation on performance, forage utilization and intake, productivity, rumen fermentation, and nutrient digestibility of growing beef cattle fed stockpiled forage. In experiment 1 (EXP1) and experiment 2 (EXP2), 45 cross bred yearling steers were managed on stockpiled crested wheatgrass pasture over 70 days during summer/fall of 2011 and 2012. Steers were stratified by IBW (EXP1 = 334±1.2 kg; EXP2 = 358±1.8 kg) and allocated randomly to 1 of 9 crested wheatgrass pastures (5 steers/pasture). Each pasture was randomly assigned to 1 of 3 replicated (n = 3) treatments. In EXP1, two isonitrogenous and isocaloric by-product feed pellets that differed in starch and degradable fiber content were used in one of three supplementation strategies: 1) no supplement (CON), or supplemented at 0.6 % of BW with 2) low starch/high fibre (LS/HF) pellet (40.3% starch; 29.5% NDF DM basis) pellet, or 3) high starch/low fibre (HS/LF; 48.6% starch; 22.8% NDF DM basis) pellet. In EXP2 a by-product feed pellet was formulated to provide ruminal and post-ruminal energy (30.3 % NDF; 32.0 % starch; 7.2 % fat) supplementation strategies included: 1) daily (DLY) supplementation at 0.6 % of BW, 2) low-alternate (LA) supplementation at 0.9 % of BW, and 3) high-alternate (HA) supplementation at 1.2 % of BW. There was no effect (P > 0.05) of treatment on forage utilization in either experiment. In EXP 1, final BW and ADG were not different (P > 0.05) between LS/HF (435 kg; 1.4 kg d-1) and HS/LF (439 kg; 1.5 kg d-1). However, supplemented cattle had higher (P < 0.05) final BW and ADG than CON cattle (402 kg; 1.0 kg d-1). Supplementation increased production costs by 450 %. In EXP 2, no difference (P > 0.05) was observed for final BW and ADG among DLY (435 kg; 1.1 kg d-1), LA (424 kg; 0.9 kg d-1), and HA (428 kg; 1.0 kg d-1). Production costs were reduced by 23 % with alternate supplementation and LA had 19 % less production costs than HA. In experiment three (EXP 3), four ruminally cannulated beef heifers were individually fed a stockpiled grass hay and offered the same pelleted supplement as in EXP2. Treatments consisted of 4 supplementation strategies: 1) no supplement (CON), 2) daily (DLY) supplementation at 0.6% BW, 3) low-alternate (LA) supplementation at 0.9 % of BW, and 4) high-alternate (HA) supplementation at 1.2 % of BW. Forage intake, rumen fermentation parameters, and apparent total tract digestibility were measured. Three data sets were analyzed: 1) overall (average of all collection days), 2) day of supplementation (DS) and 3) non-supplementation day (NSD) for alternating treatments. Overall, hay DMI (kg d-1) was lower (P = 0.04) for DLY (7.1) vs. CON (8.1), but no different (P ≥ 0.11) for DLY vs. LA (6.9), or vs. HA (6.4). On DS, hay DMI (kg d-1) of DLY (7.3) differed (P < 0.05) vs. HA (6.0), but was not different (P = 0.16) vs. LA (6.4). On NSD, hay DMI (kg d-1) of DLY (7.0) was not different (P ≥ 0.48) to those of LA (7.3) and HA (6.9). Overall, total VFA concentration (mM) was lower (P < 0.01) for CON (69.2) vs. DLY (77.1); but not different (P ≥ 0.45) for DLY vs. LA (75.8) or HA (75.1). Rumen NH3 (mg/dL) was lower (P < 0.01) for CON (3.4) and higher (P < 0.01) for LA (5.8) vs. DLY (4.6), but not different (P = 0.37) for DLY vs. HA (4.3). Overall, ruminal pH was lower (P ≤ 0.04) for DLY (6.65) vs. CON (6.75) and HA (6.72), but similar (P = 0.18) for DLY vs. LA (6.70). On DS, ruminal pH was lower (P = 0.04) for HA (6.59) vs. DLY (6.64), but higher (P < 0.01) on NSD for HA (6.85) vs. DLY (6.67). Apparent DM, OM and GE digestibility coefficients were lower (P ≤ 0.03) for CON and LA vs. DLY, but no difference (P ≥ 0.36) for DLY vs. HA. These results indicate that beef steers grazing stockpiled crested wheatgrass were limited in energy intake and that supplementation of metabolizable energy improved animal performance regardless of the source of energy. Reducing the frequency of energy supplementation and level offered on alternate days do not affect animal performance and reduces the production costs of the system. Negative effects of alternate day supplementation on forage intake and rumen fermentation are reduced when a lower level is offered relative to simply doubling the daily amount of supplement.
128

Understanding Beef Cattle Efficiency: I) Understanding Physiological and Digestive Factors Affecting Residual Feed Intake and II) Tannin Supplementation: Effects on Animal Performance, Fermentation, and Carcass Traits

Krueger, Wimberley K. 2009 August 1900 (has links)
Objectives of this study were 1) to characterize the relationship between beef cattle efficiency, namely residual feed intake (RFI), and digestive, microbial, and fermentation parameters in growing beef calves and 2) to examine the effects of added dietary hydrolysable or condensed tannin on animal performance and efficiency, fermentation and carcass and non-carcass traits. To accomplish the first objective, multiple RFI studies were conducted and in all studies RFI was calculated as the difference between actual and expected dry matter intake (DMI) based on average gaily gain (ADG) and body weight0.75(BW). A total of 187 head selected out of a population of 600 head of growing beef calves were evaluated for diet and nutrient digestibility, ruminal and fecal volatile fatty acids (VFA) concentrations and methane producing activity (MPA). Low RFI calves consumed less DMI and had lower feed conversion ratios (FCR) as compared to high RFI calves. Low RFI calves also had higher diet and nutrient digestibilities compared to high RFI calves. Residual feed intake was negatively correlated with diet and nutrient digestibilities such that more efficient animals had higher digestibilities. Low RFI calves tended to have lower ruminal propionate and higher acetate:propionate ratios when fed a high-forage diet. Calves with divergent RFI did not have different gross microbial populations as evidenced by the Firmicute:Bacteriodetes ratio, but low RFI calves tended to have higher fecal Prevotella spp. and lower fecal Spirochaetes and ruminal Cyanobacteria. The importance of these subtle shifts in microbial ecology is not evident at this time and more research is needed to fully elucidate the interaction of host and microbes to fully grasp the importance of minor microbial deviations. No differences in 3 h MPA were detected in low vs. high RFI calves but low RFI calves had higher fecal MPA when sampled at 24 h; however, calculated methane emissions were lower for low RFI calves. Tannin supplementation had no effect on animal performance and efficiency, ruminal fermentation VFA concentrations, MPA, or ammonia concentrations in finishing beef steers. There was also no detrimental effect of tannins on carcass traits; however, hydrolysable tannin supplementation resulted in increased empty rumen mass. Results from these studies indicate that diet and nutrient digestibility are affected by RFI such that more efficient calves had higher DMD, microbial ecology is responsive to RFI such that minor microbial shifts were observed, and tannin supplementation, at the current inclusion rate, had no effect on animal and carcass performance.
129

Characterization of Feeding Behavior Traits and Associations with Performance and Feed Efficiency in Finishing Beef Cattle

Mendes, Egleu Diomedes Marinho 2010 August 1900 (has links)
The first objective of this study was to validate the feeding behavior measurements from a radio frequency electronic system (GrowSafe (TM) System Ltd., Airdrie, AB, Canada) and examine the software sensitivity to different parameter settings (MPS) to quantify feeding behavior traits. Data was continuously recorded 24 h per day using the GrowSafe™ system for 32 heifers over 81-d. Ten animals were randomly selected and evaluated over 6-d using time-lapse video recordings. Different parameter settings (MPS) from the electronic system (GrowSafe (TM)) used to record feeding behavior data, bunk visits (BV) frequency and BV duration, were compared with the observed (video) values. The second objective of this study was to quantify meal criterion; examine the associations between feeding behavior traits, performance, and feed efficiency; and the effects of breed type on feed efficiency (residual feed intake - RFI) and feeding behavior traits in heifers fed high-grain diets. Results from study one demonstrated that the GrowSafe (TM) system 4000E could accurately predict BV and meal data compared to observed data. The 100 s, used for the maximum duration between consecutive EID recordings to end an uninterrupted BV, was the appropriate MPS to predict BV frequency and duration, and meal frequency and duration compared to observed data using the GrowSafe (TM) 4000E system. The system’s ability to detect the animal’s presence or absence at the feed bunk was 86.4 and 99.6 percent, respectively. Results from the second study demonstrated that the meal criterion for heifers fed high-grain diets was 13.8 min. The 4 methods to calculate meal criterion demonstrated no differences in results of frequencies and durations of meal and the number of bunk visits per meal. Similar phenotypic correlations were found between the feeding behavior traits with RFI derived from the base model or with adjustments for final back fat. The adjustment of RFI to final back fat changed the RFI rank between breeds. The addition of feeding behavior traits to the RFI base model could accounted up to 40.4 percent of the variation in DMI not explained by ADG or MBW.
130

Ovarian and hormonal events during synchronization of ovulation and timed appointment breeding of Bos indicus-influenced cattle using intravaginal progesterone, GnRH and prostaglandin F2(alpha)

Saldarriaga Lopez, Juan Pablo 25 April 2007 (has links)
Objectives were to 1) evaluate the use of the CO-Synch + CIDR (COS-C) protocol for synchronization of ovulation and timed AI (TAI) in Bos indicus-influenced cattle, 2) compare cumulative pregnancy rates after COS-C synchronization and TAI to those in a traditional management (TM) scheme, and 3) evaluate specific ovarian, hormonal, and estrual events associated with COS-C. The COS-C regimen included insertion of a controlled internal drug release device (CIDR) containing progesterone and injection of GnRH (GnRH-1) on day 0, removal of the CIDR and injection of prostaglandin F2a (PGF on d 7, and injection of GnRH (GnRH-2) and TAI 48 h later. In experiment 1 (Exp. 1), 335 females were stratified by BCS, parity and d postpartum before random assignment to COS-C or TM. An additional 96 females in which TM controls were not available for comparison also received COS-C. Conception rates to TAI averaged 39% (n = 266). Cumulative pregnancy rates were greater (P < 0.05) after 30 and 60 d of the breeding season in COS-C than in TM (n = 170 and 165 females respectively). In experiment 2 (Exp. 2), 100 postpartum (F1) females were stratified as in Exp. 1 within four replicates (25 each) and assigned randomly to receive either COSC or COS (no CIDR) treatment. No differences were observed between treatments and all data were pooled. Percentages of cows ovulating after GnRH-1, developing a synchronized follicular wave, exhibiting luteal regression to PGF, and ovulating to GnRH-2 were 40, 60, 93, and 72%, respectively. In experiment 3 (Exp. 3), primiparous (F1) heifers (n = 32) and pluriparous cows (n = 18) received the Select Synch + CIDR synchronization regimen (no GnRH-2 or TAI). Mean intervals from CIDR removal to estrus and ovulation, and from estrus to ovulation were 70 ± 2.9, 99 ± 2.8, and 29 ± 2.2 h, respectively. Relatively low TAI conception rates (< 50%) were attributed to failure of 40% of cattle to develop a synchronized follicular wave after GnRH-1 and to inappropriate timing of TAI/GnRH-2. It may be possible to improve TAI conception rates by delaying TAI/GnRH-2 to between 66 and 72 h, and by developing methods to increase the number of ovulations after GnRH-1.

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